The engine runs fine. When the problem occurs the engine smoothly gains RPM up to the shifting point to go to 3rd (I belive it's 3rd since 1st is bypassed?) and then kicks back down. It ends up feeling like a learching motion.
Some background, since I have what I believe are full service records:
- Car is a '94 purchased 11/93. I purchased 11/96.
- Service record on 5/3/95 at 21813 miles indicates the loss of power for the first time. The dealer performed a number of engine tests at that time.
- Service record 5/17/95 indicates another episode of loss of power. Looks like they replaced the ignition coils at that time.
- No further mention of the problem in the previous owner's service sheets
- 10/1/97 Car lost power while driving on the interstate. After sitting with the engine off for a while it functioned properly. Took the car to a dealer and they replaced the overvoltage protection relay. Part number listed on the invoice is 000-540-67-45 (I do not know if that's a Mercedes's number or just the dealer's stock number).
- Since that time the car has acted up on at least a half dozen occasions, the lastest of which was this past weekend. The last time we visited a dealer they recommended letting the car sit for 15 minutes so "everything could reset." Tried both disconnecting the battery and letting the car sit for 30 minutes; neither worked... the car was fine the next morning.
The only other odd thing I've noticed is that when the car is driven for the first time on a given day, it seems reluctant to get into 3rd gear (again, assuming 1st is bypassed, so this would be the first shift for the tranny). Gradually accelerating, I have to speed up sufficiently to raise the RPM up into the 2000-3000 range to get it to make the first shift. After this first episode, it shifts smoothly at lower RPM. I this normal for these cars?
Finally, I mistakenly put down '93 in my original post; the car is a '94 E320.
Much appreciate the feedback and assistance.